Radeon HD 3850 512MB vs Radeon HD 4850 2GB

Intro

Compare those specifications to the Radeon HD 4850 2GB, which features a core clock frequency of 625 MHz and a GDDR4 memory speed of 993 MHz. It also features a 256-bit memory bus, and makes use of a 55 nm design. It is made up of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3850 512MB		75 Watts
Radeon HD 4850 2GB		110 Watts
	Difference: 35 Watts (47%)

Memory Bandwidth

The Radeon HD 4850 2GB, in theory, should be a little bit faster than the Radeon HD 3850 512MB in general. (explain)

Radeon HD 4850 2GB		63552 MB/sec
Radeon HD 3850 512MB		52992 MB/sec
	Difference: 10560 (20%)

Texel Rate

The Radeon HD 4850 2GB should be quite a bit (about 134%) faster with regards to texture filtering than the Radeon HD 3850 512MB. (explain)

Radeon HD 4850 2GB		25000 Mtexels/sec
Radeon HD 3850 512MB		10688 Mtexels/sec
	Difference: 14312 (134%)

Pixel Rate

The Radeon HD 3850 512MB is a bit (approximately 7%) faster with regards to AA than the Radeon HD 4850 2GB, and will be able to handle higher screen resolutions more effectively. (explain)

Radeon HD 3850 512MB		10688 Mpixels/sec
Radeon HD 4850 2GB		10000 Mpixels/sec
	Difference: 688 (7%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of information (counted in MB per second) that can be transported past the external memory interface within a second. It is worked out by multiplying the interface width by its memory clock speed. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This is worked out by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly write to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.